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我想根据标签的高度动态设置单元格的高度。

我创建了单元格：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *simpleTableIdentifier = @"ORDStepsCell";

UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];

UILabel *stepsLabel;
UILabel *stepsNumberLabel;
UIImageView *bulletImageView;
UIImageView *cellBackgroungImage;

if (cell == nil) {
    cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:simpleTableIdentifier];

    CGRect stepsLabelFrame = CGRectMake(20, 0, 253, 21);
    CGRect bulletImageViewFrame = CGRectMake(281, 25, 29, 29);;
    CGRect stepsNumberLabelFrame = CGRectMake(3, 3, 21, 21);
    CGRect cellBackgroungImageFrame = CGRectMake(0, 0, 320, 80);

    cellBackgroungImage = [[UIImageView alloc] initWithFrame:cellBackgroungImageFrame];
    cellBackgroungImage.image = [UIImage imageNamed:@"list-item"];

    stepsLabel = [[UILabel alloc] initWithFrame:stepsLabelFrame];
    stepsLabel.textAlignment = UITextAlignmentRight;
    stepsLabel.tag = 0;

    bulletImageView = [[UIImageView alloc] initWithFrame:bulletImageViewFrame];
    bulletImageView.image = [UIImage imageNamed:@"step-bullet"];

    stepsNumberLabel = [[UILabel alloc] initWithFrame:stepsNumberLabelFrame];
    stepsNumberLabel.textAlignment = UITextAlignmentCenter;
    stepsNumberLabel.textColor = [UIColor whiteColor];
    stepsNumberLabel.backgroundColor = [UIColor clearColor];
    stepsNumberLabel.font = [UIFont boldSystemFontOfSize:17.0];
    stepsNumberLabel.tag = 1;

    [cell.contentView addSubview:cellBackgroungImage];
    [cell.contentView addSubview:stepsLabel];
    [cell.contentView addSubview:bulletImageView];
    [bulletImageView addSubview:stepsNumberLabel];

} else {
    stepsLabel = (UILabel *)[cell viewWithTag:0];
    stepsNumberLabel = (UILabel *)[cell viewWithTag:1];
}

stepsLabel.text = [preperationSteps objectAtIndex:indexPath.row];
[stepsLabel setBackgroundColor:[UIColor redColor]];
[stepsLabel setNumberOfLines:0];
[stepsLabel sizeToFit];

NSLog(@"cellHeight = %f", cell.frame.size.height);

stepsLabel.frame = CGRectMake(20, (cell.frame.size.height - stepsLabel.frame.size.height) / 2, 253, stepsLabel.frame.size.height);

stepsNumberLabel.text = [NSString stringWithFormat:@"%d", indexPath.row + 1];

[cell setSelected:NO];
[cell setSelectionStyle:UITableViewCellEditingStyleNone];

return cell;

}

然后我计算了标签的高度：

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
UILabel *cellLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 253, 30)];
NSString *labelText = [preperationSteps objectAtIndex:indexPath.row];
cellLabel.text = labelText;
[cellLabel setNumberOfLines:0];

[cellLabel sizeToFit];

cellLabel.frame = CGRectMake(0, 0, 253, cellLabel.frame.size.height);
CGFloat cellLabelHeight = cellLabel.frame.size.height;
NSLog(@"cellLabelHeight = %f", cellLabelHeight + 20);
return cellLabelHeight + 20;
}

在日志中：

2013-03-08 17:37:18.161 Recipe[37547:c07] cellLabelHeight = 125.000000
2013-03-08 17:37:18.161 Recipe[37547:c07] cellLabelHeight = 62.000000
2013-03-08 17:37:18.161 Recipe[37547:c07] cellLabelHeight = 41.000000
2013-03-08 17:37:18.162 Recipe[37547:c07] cellLabelHeight = 41.000000
2013-03-08 17:37:18.162 Recipe[37547:c07] cellLabelHeight = 41.000000
2013-03-08 17:37:18.162 Recipe[37547:c07] cellLabelHeight = 41.000000
2013-03-08 17:37:18.163 Recipe[37547:c07] cellLabelHeight = 62.000000
2013-03-08 17:39:34.852 Recipe[37581:c07] cellHeight = 44.000000
2013-03-08 17:39:34.852 Recipe[37581:c07] cellHeight = 44.000000
2013-03-08 17:39:34.853 Recipe[37581:c07] cellHeight = 44.000000
2013-03-08 17:39:34.853 Recipe[37581:c07] cellHeight = 44.000000
2013-03-08 17:39:34.854 Recipe[37581:c07] cellHeight = 44.000000
2013-03-08 17:39:34.854 Recipe[37581:c07] cellHeight = 44.000000
2013-03-08 17:39:34.855 Recipe[37581:c07] cellHeight = 44.000000

如您所见，即使从 heightForRowAtIndexPath 返回的值不同，单元格的高度也是固定的 44。我知道在 cellForRowAtIndexPath 之前调用了 heightForRowAtIndexPath （如日志中所示），那么如何更改高度？

4

3 回答 3

1

您给出的高度就是heightForRowAtIndexPath显示的高度。将此代码粘贴到您的控制器中，然后查看您实际显示的高度。

-(void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {
    NSLog(@"%f", cell.frame.size.height);
}

您登录的cellForRowAtIndexPath高度只是单元格的默认高度。高度在cellForRowAtIndexPath被调用后被分配。

于 2013-03-08T16:04:34.633 回答
0

对我来说解决问题的是使用and方法计算标签的文本长度sizeWithFont:constrainedToSize:lineBreakMode: ，然后使用计算的大小设置标签的框架。 如果它对任何人有任何帮助，我将发布代码。cellForRowAtIndexPathheightForRowAtIndexPathcellForRowAtIndexPath

于 2013-03-09T12:37:05.907 回答
0

我想根据标签的高度动态设置单元格的高度。

您可能想要这样，但您没有在-tableView:cellForRowAtIndexPath:方法中的任何位置设置单元格高度。-tableView:heightForRowAtIndexPath:不会为您设置单元格的高度 - 您需要在以前一种方法配置单元格时执行此操作。后一种方法的原因是桌子可以确定自己的高度。每当它重新加载数据时，它都会向代理询问每一行的高度，并使用该信息来计算表格的总高度。每次为给定行提供单元格时，您仍然必须设置单元格高度。

于 2013-03-08T16:44:01.367 回答